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Quercetin and curcumin are well-known natural antioxidant molecules used to prevent the malignant effect caused by free radicals on biological systems. This work addressed the creation of eutectic mixtures from...

Pt2RuMo/C catalysts were synthesized by the modified polyol method in the presence and absence of Li(C2H5)3BH (LBH), annealed at 600 °C under H2 atmosphere to improve the reduction of Pt and Ru to provide stronger interactions between Mo and another metals. LBH affected the physico-chemical characteristics of Pt2RuMo, that is, in the presence of LBH an increment of Mo(IV) amount and a decrease in the PtRu alloying degree were observed. The catalytic activity for hydrogen oxidation in the presence and absence of CO (CO tolerance) of the Pt2RuMo/C catalysts as anodes in polymer electrolyte membrane fuel cells (PEMFCs) was compared to that of a commercial PtRu/C catalyst. The results indicated that the CO tolerance increased with an increase in Mo(IV) content, but the stability increased with an increment of the amount of Ru oxides in the catalysts.

Pt electrocatalysts supported on pristine graphene nanosheets (GNS) and nitrogen-doped graphene nanoplatelets (N-GNP) were prepared through the ethylene glycol process, and a comparison of their CO tolerance and stability as anode materials in polymer electrolyte membrane fuel cells (PEMFCs) with those of the conventional carbon (C)-supported Pt was made. Repetitive potential cycling in a half cell showed that Pt/GNS catalysts have the highest stability, in terms of the highest sintering resistance (lowest particle growth) and the lowest electrochemically active surface area loss. By tests in PEMFCs, the Pt/N-GNP catalyst showed the highest CO tolerance, while the poisoning resistance of Pt/GNS was lower than that of Pt/C. The higher CO tolerance of Pt/N-GNP than that of Pt/GNS was ascribed to the presence of a defect in graphene, generated by N-doping, decreasing CO adsorption energy.